Thanks Tom, MarcG, ReorX

for putting effort to reply back

Well the problem is clearly visible in the figure which i am enumerating as following:
1.0 Y axis values:
In fft calculation from my routine i am getting values in power of 10pow+3 with magnitude of max value upto 7000 , while for other routine from DAOS values are in the range of 10pow-1 and value of max value about 4*10-3

This is remarkable difference

2.0 On the X axis, it can be viewed that point of max in my routine calculation occurs at position 16th while with DAOS it comes to be about 4.

So these are main reason of my problem.

I had even tried the code from Numerical Reciepe in C, but it too provides similar outputs as FFTReal routine, which i am using.

Kindly provide your kind inputs.

Thanking You

Sandeep Arya